Behuria Himadri Gourav, Arumugam Gandarvakottai Senthilkumar, Pal Chandan Kumar, Jena Ashis Kumar, Sahu Santosh Kumar
Department of Biotechnology, Maharaja Sriram Chandra Bhanj Deo University (Erstwhile: North Orissa University), Mayurbhanj, Baripada, Odisha 757003, India.
Bioengineering and Drug Design Lab, Department of Biotechnology, IIT Madras, Chennai 6000 36, India.
ACS Omega. 2021 Dec 16;6(51):35667-35678. doi: 10.1021/acsomega.1c05581. eCollection 2021 Dec 28.
An amphiphilic phytochemical fraction isolated from methanol extract of leaf powder contained six terpenoids, two flavonoids, and one alkaloid that induced rapid flip-flop of fluorescent phospholipid analog in the phosphatidyl choline bilayer. Lipid-flipping activity of the methanol-extracted fraction of (MEFGS) was dose-dependent and time-dependent with a rate constant = (12.09 ± 0.94) mg min that was saturable at (40 ± 1) % flipping of the fluorescent lipid analogue. Interactions of MEFGS phytochemicals with large unilamelar vesicles led to time-dependent change in their rounded morphology into irregular shapes, indicating their membrane-destabilizing activity. MEFGS exhibited antibacterial activity on (MTCC-118), (MTCC-212), and (MTCC-1035) with IC values 0.5, 0.35, and 0.1 mg/mL, respectively. Phytochemicals in MEFGS increased membrane permeabilization in all three bacteria, as indicated by 23, 17, and 17% increase in the uptake of crystal violet, respectively. MEFGS enhanced membrane damage, resulting in a 3-5 fold increase in leakage of cytosolic ions, 0.5-2 fold increase in leakage of PO , and 15-20% increase in loss of cellular proteins. MEFGS synergistically increased the efficacy of curcumin, amoxillin, ampicillin, and cefotaxime on probably by enhancing their permeability into the bacterium. For the first time, our study reveals that phytochemicals from enhance the permeability of the bacterial plasma membrane by facilitating flip-flop of membrane lipids. Lipid-flipping phytochemicals from can be used as adjuvant therapeutics to enhance the efficacy of antibacterials by increasing their bioavailability in the target bacteria.
从叶粉甲醇提取物中分离出的一种两亲性植物化学成分馏分含有六种萜类化合物、两种黄酮类化合物和一种生物碱，它们能诱导磷脂酰胆碱双层中荧光磷脂类似物快速翻转。甲醇提取物馏分（MEFGS）的脂质翻转活性具有剂量依赖性和时间依赖性，速率常数为（12.09±0.94）mg/min，在荧光脂质类似物翻转（40±1）%时达到饱和。MEFGS植物化学成分与大单层囊泡的相互作用导致其圆形形态随时间变化为不规则形状，表明其具有膜 destabilizing 活性。MEFGS对金黄色葡萄球菌（MTCC - 118）、大肠杆菌（MTCC - 212）和枯草芽孢杆菌（MTCC - 1035）具有抗菌活性，IC值分别为0.5、0.35和0.1mg/mL。MEFGS中的植物化学成分使所有三种细菌的膜通透性增加，分别表现为结晶紫摄取量增加23%、17%和17%。MEFGS增强了膜损伤，导致胞质离子泄漏增加3 - 5倍、磷酸根泄漏增加0.5 - 2倍以及细胞蛋白质损失增加15 - 20%。MEFGS可能通过增强姜黄素、阿莫西林、氨苄青霉素和头孢噻肟对大肠杆菌的通透性，协同提高了它们的疗效。我们的研究首次揭示，来自某植物的植物化学成分通过促进膜脂翻转来增强细菌质膜的通透性。来自某植物的脂质翻转植物化学成分可作为辅助治疗剂，通过提高抗菌药物在靶细菌中的生物利用度来增强其疗效。
